I have installed a few ... tho my personal 124 still has it's OEM aluminum blade.The feel is a tad firmer due to no flex, but internally in how the blade articulates the sear mechanics remain the same pretty much IMO.I've found 124/127's differ some, in that some can be adjusted to a Bump/Hang as if in a notch on second stage almost like a double set trigger, where others won't.